Dual engine air and land multimodal vehicle

ABSTRACT

An air and land multimodal vehicle comprises a frame, a propeller engine attached to a first location of the frame supplying power and torque to a propeller, a ground engine attached to a second location of the frame supplying power and torque to one or more ground traction elements, and a flexible wing releasably connectable to the frame, wherein the propeller engine is vertically and horizontally spaced from the ground engine and the ground engine extends at least six inches below a base of the frame.

CROSS REFERENCE TO RELATED APPLICATIONS/PRIORITY

The present invention is a continuation from International PatentApplication Number PCT/US2016/043613 filed Jul. 22, 2016, which claimspriority and benefit to U.S. Provisional Patent Application No.62/358,353 filed Jul. 5, 2016, each of the above applications isincorporated by reference into the present disclosure as if fullyrestated herein. To the extent that there is any conflict between theincorporated material and the present disclosure, the present disclosurewill control.

BACKGROUND

Military and first responders have needs for transporting individualsinto areas inaccessible by roads, and then maneuvering quickly on theground over rough terrains, and then quickly and with minimal takeoffroom, exiting the area. No vehicle has as of yet been devised that meetsall of these requirements. For the foregoing reasons, there is apressing, but seemingly irresolvable need for a vehicle with suchfunctionality.

SUMMARY

Wherefore, it is an object of the present invention to overcome theabove mentioned shortcomings and drawbacks associated with the currenttechnology.

The present invention relates to methods and devices for air and landmultimodal vehicles comprising a frame, a propeller engine attached to afirst location of the frame supplying power and torque to a propeller, aground engine attached to a second location of the frame supplying powerand torque to one or more ground traction elements, and a flexible wingreleasably connectable to the frame, wherein the propeller engine isvertically and horizontally spaced from the ground engine.

According to an additional embodiment, the flexible wing is a ram airparafoil, the ground engine does not supply torque to the propeller, andthe propeller engine does not supply torque to the one or more groundtraction elements.

According to an additional embodiment, the propeller engine and theground engine are both aligned with a vertically extending medial planeof the multimodal vehicle bisecting the multimodal vehicle from thefront of the vehicle to the back of the vehicle.

According to an additional embodiment, a horizontal rear axle planeextends parallel to the ground, and a rear axle and the ground enginelie in the horizontal rear axle plane. A continuously variabletransmission may functionally connect the ground engine to the rearaxle, and the continuously variable transmission may lie in the rearaxle plane. It is understood that a standard transmission, includingstick or paddle shift, or other automatic transmission may be used inthe presently claimed invention. A drive shaft may extend from thecontinuously variable transmission and connect to a differential of therear axle, the drive shaft transmitting power and torque from thecontinuously variable transmission to the rear axle and ground tractionelements of the multimodal vehicle. The drive shaft may lie in the rearaxle plane.

According to an additional embodiment, each of the propeller engine andthe ground engine provides at least one of 65 horse power and at least50 ft-lbs torque.

According to an additional embodiment, a surface area of the ram airparafoil is between 300 square feet and 650 square feet, and preferablybetween 500 square feet and 600 square feet.

According to an additional embodiment, one or more passenger seats arealigned with a vertically extending medial plane bisecting themultimodal vehicle from the front of the vehicle to the back of thevehicle. A first passenger seat and a second passenger seat may each besubstantially bisected by the medial plane. The second passenger seatmay be horizontally behind the first passenger seat and may be between 6and 18 inches vertically higher than the first passenger seat, asmeasured from the substantially horizontal sitting portion of the seat.

While a propeller guard may be used, according to an additionalembodiment, the propeller lacks a propeller guard.

According to an additional embodiment, the propeller engine and theground engine operate on a same or common fuel. The propeller engine andthe ground engine may be fluidly connected to a common fuel reservoir.

According to an additional embodiment, the ground engine extends atleast 6 inches below a base of the frame and a base guard extends underthe ground engine to protect the ground engine.

According to an additional embodiment, the propeller engine extends atbetween 3 inches and 8 inches behind a farthest portion of frame; apropeller centerline is between 15 inches and 25 inches above the groundengine, and the propeller engine is spaced 28 inches behind groundengine.

According to an additional embodiment, a takeoff distance is less than300 feet, where takeoff is when the multimodal vehicle is supported bythe wing and the ground traction elements are not in contact with theground, directly followed by a substantially prolonged period of flight,of, for example, greater than 10 minutes, but more preferably greaterthan 30 minutes.

According to an additional embodiment, the multimodal vehicle has a dryweight of between 1,000 lbs and 1,450 lbs, preferably between 1,050 lbsand 1,200 lbs and more preferably between 1,075 lbs and 1,125 lbs, andthe ground traction elements are one of wheels and tracks.

The multimodal vehicle is an ultimate first response, military, orrecreational vehicle combining off-road functionality and adventure withpowered paragliding freedom from roads. It can be transformed from apowersports off road vehicle to a light-sports aircraft in a matter ofminutes using ram-air parafoil wing technology. With relatively shorttakeoff and landing needs, open fields, grass strips and secludedbeaches become possible runways. Once airborne, the multimodal vehiclecan preferably reach air speeds of at least 50 mph, and can soar ataltitudes of 3,000 feet or more. The multimodal vehicle is also anultimate sightseeing recreational aircraft that offers an exhilaratingexperience and true sense of adventure. The multimodal vehicle allowspilots to see the world from a low vantage point that is not safelyattainable by most fixed-wing airplanes.

According to one embodiment the body has an angular appearance andexposed tubular exoskeleton, the multimodal vehicle is stylishlycapable, without compromise. The body construction uses seamlessair-hardened, heat-treated steel tubing to achieve immense strengthallied to lower weight penalties. The open architecture delivers astripped back driving experience that leaps into the cockpit for anexhilarating ride expressively combining sporty handling with a balancethat is surefooted and stable. The multimodal vehicle's preferablepressurized-nitrogen inverted double wishbone suspension partners itsinherent chassis/frame control, which helps in handling either roughroads or sharp corners with equal poise and supple precision.

Similar to a fighter jet, according to one embodiment, pilot andpassenger are seated in-line for optimal performance and balance. Themultimodal vehicle's open cockpit design provides superb high-visibilityfor increased safety and enjoyment of the world around the pilot. Thelogical instrument layout, preferably devoid of distracting dials,switches and buttons keeps the pilot focus where it belongs—outside.

Once airborne, the multimodal vehicle preferably has only two flightcontrols—handles for left and right steering (roll) and a throttlehandle or pedal to climb or descend (pitch). This intuitive flightsystem makes the multimodal vehicle one of the easiest and safest formsof flight to master and offers an unmatched flying experience.

The Following Six Paragraphs Describe a Preferred Embodiment:

The frame is constructed of a 41xx steel, such as 4130 chromoly steel,with a 1.5″ diameter roll cage. There is an adjustable steering wheel.The front suspension has 9″ travel dual A-arm with Fox™ 1.5 Podium™shocks. The rear suspension has 12″ travel dual A-arm with Fox™ 2.0Podium™ C shocks. The front tires are Maxxis Bighorn™ Radial ATV Tire29×9-14. The rear tires are Maxxis Bighorn™ Radial ATV Tire 29×11-14,and the wheels are Aluminum. The multimodal vehicle seats two inline.

The dry weight of the multimodal vehicle is approximately 1,100 lbs (500kg), but can be more with optional equipment added. Thelength×width×height may measure approximately 162″×72″×77″ (426 cm×183cm×195 cm). The wheelbase is approximately 72″ (183 cm). The groundclearance from the ground to the base of the frame is approximately13″-15″ (38 cm). The payload capacity is preferably a minimum of 350 lbs(159 kg) and a maximum of 600 lbs. The two fuel tanks preferably hold aminimum of 15 gal (56 L) and a maximum of 45 gal.

The multimodal vehicle preferably includes a PD Sunriser 550 ram-airparafoil wing. The propeller engine is monitored with an enginemonitoring system (EMS) with a Dynon™ D-10. A VHF Radio is preferablyincluded, along with light emitting diode (LED, Position & StrobeLights, Aux 1, Aux 2, Aux 3, and Aux 4 rocker switched. The throttle isa throttle quadrant with mixture control. Preferably an altimeter ratedto 20,000 ft is included.

The multimodal vehicle preferably has a maximum ground speed of at least70 mph 61 knots 112 k/h, a maximum air speed of at least 50 mph 43 knots80 k/h, an average or cruising air speed of 40 mph 34.7 knots 64 k/h, aground range of at least 240 miles (386 km) per fuel fill up, a flightrange of at least 140 miles (225 km) per fuel fill up, a takeoff andlanding distance of 300 ft MSL or less, and a thrust of at least 525 lbs(238 kg).

According to the described embodiment the propeller engine is a 100 hpRotax™ 912 ULS, 4 cylinder, 4 stroke with opposed cylinders, acarbureted fuel system and 135 cc of displacement. The propeller engineis cooled with liquid and air, has a gearbox, integrated reduction gearwith a gear ratio of 2.43 (i=2.43), and an electric starter. The flightinstrumentation preferably includes Oil Temp, Oil Pressure, Fuel, Amps,RPM, EGT, CHT, Coolant Temp, Coolant Pressure, OAT, Carb Temp, andVolts. The propeller engine has a takeoff speed approximately 5,800 rpm(5 min. max), a maximum continuous speed of approximately 5,500 rpm, andan idle speed of approximately 1,400 rpm. The maximum safe cylinder headtemperature (CHT) is around 150 C (300 F). The exhaust gas temperatureis normal at 1,472 F and has a maximum at 1,652 F, measured 4-6″ fromthe exhaust valve and 2″ from the propeller engine. The coolant pressureis preferably 12-17 PSI, normal 58 PSI, maximum 72 PSI, minimum 22 PSI @2,800 rpm, and with a cold start the max is 102 PSI. The most favorableoperating oil temperature is between 190-230 F (90-110 C). The fuelpressure is preferably 5.8 PSI.

According to the described embodiment, the ground engine is an 89 hp,4-Stroke single overhead cam (SOHC) Twin Cylinder, 952 cc, liquidcooled, electronic fuel Injected engine. The drivetrain is preferablytwo wheel drive (2WD) (preferably rear wheels), but it may be convertedto a front wheel drive or a four wheel drive (4WD). There is preferablya digital screen control, with a digital gauge, speedometer, odometer,global positioning system (GPS) touchscreen tachometer, two trip meters,Hour Meter, Clock, Service Time, Diagnostic Indicator, Gear Indicator,Fuel Gauge, Hi-Temp/Low-Batt Lights, and a direct current (DC) Outlet.

Various objects, features, aspects, and advantages of the presentinvention will become more apparent from the following detaileddescription of preferred embodiments of the invention, along with theaccompanying drawings in which like numerals represent like components.The present invention may address one or more of the problems anddeficiencies of the current technology discussed above. However, it iscontemplated that the invention may prove useful in addressing otherproblems and deficiencies in a number of technical areas. Therefore theclaimed invention should not necessarily be construed as limited toaddressing any of the particular problems or deficiencies discussedherein.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate various embodiments of theinvention and together with the general description of the inventiongiven above and the detailed description of the drawings given below,serve to explain the principles of the invention. It is to beappreciated that the accompanying drawings are not necessarily to scalesince the emphasis is instead placed on illustrating the principles ofthe invention. The invention will now be described, by way of example,with reference to the accompanying drawings in which:

FIG. 1 is a schematic front plan view of a multimodal vehicle accordingto the present invention, with the seats not shown for added clarity;

FIG. 2 is a schematic cross-sectional side plan view the multimodalvehicle of FIG. 1 in the direction marked F2, with the wing omitted; and

FIG. 3 is a schematic top plan view of the multimodal vehicle of FIG. 1with the wing omitted for clarity.

DETAILED DESCRIPTION

The present invention will be understood by reference to the followingdetailed description, which should be read in conjunction with theappended drawings. It is to be appreciated that the following detaileddescription of various embodiments is by way of example only and is notmeant to limit, in any way, the scope of the present invention. In thesummary above, in the following detailed description, in the claimsbelow, and in the accompanying drawings, reference is made to particularfeatures (including method steps) of the present invention. It is to beunderstood that the disclosure of the invention in this specificationincludes all possible combinations of such particular features, not justthose explicitly described. For example, where a particular feature isdisclosed in the context of a particular aspect or embodiment of theinvention or a particular claim, that feature can also be used, to theextent possible, in combination with and/or in the context of otherparticular aspects and embodiments of the invention, and in theinvention generally. The term “comprises” and grammatical equivalentsthereof are used herein to mean that other components, ingredients,steps, etc. are optionally present. For example, an article “comprising”(or “which comprises”) components A, B, and C can consist of (i.e.,contain only) components A, B, and C, or can contain not only componentsA, B, and C but also one or more other components. Where reference ismade herein to a method comprising two or more defined steps, thedefined steps can be carried out in any order or simultaneously (exceptwhere the context excludes that possibility), and the method can includeone or more other steps which are carried out before any of the definedsteps, between two of the defined steps, or after all the defined steps(except where the context excludes that possibility).

The term “at least” followed by a number is used herein to denote thestart of a range beginning with that number (which may be a range havingan upper limit or no upper limit, depending on the variable beingdefined). For example “at least 1” means 1 or more than 1. The term “atmost” followed by a number is used herein to denote the end of a rangeending with that number (which may be a range having 1 or 0 as its lowerlimit, or a range having no lower limit, depending upon the variablebeing defined). For example, “at most 4” means 4 or less than 4, and “atmost 40%” means 40% or less than 40%. When, in this specification, arange is given as “(a first number) to (a second number)” or “(a firstnumber)-(a second number),” this means a range whose lower limit is thefirst number and whose upper limit is the second number. For example, 25to 100 mm means a range whose lower limit is 25 mm, and whose upperlimit is 100 mm. The embodiments set forth the below represent thenecessary information to enable those skilled in the art to practice theinvention and illustrate the best mode of practicing the invention. Inaddition, the invention does not require that all the advantageousfeatures and all the advantages need to be incorporated into everyembodiment of the invention.

Turning now to FIG. 1, a brief description concerning the variouscomponents of the present invention will now be briefly discussed. Ascan be seen in this embodiment, the invention relates to dual engine airand land multimodal vehicles 2 comprising a propeller engine 4 poweringa propeller 6, a ground engine 8 powering ground traction elements 10such as wheels or tracks, and a flexible wing 12. The propeller engine 4and the ground engine 8 are separately mounted and provide separatepower. The multimodal vehicle 2 preferably has at least a first seat 14for one passenger aligned with a midline plane 16 of the multimodalvehicle 16, or a first and a second seat 14, 18 for two passenger,preferably in arranged tandem with both seats 14, 18 aligned with themidline plane 16 of the multimodal vehicle 2. If there are twopassengers, the passenger in the front first seat 14 is preferably thedriver and the passenger in the back second seat 18 preferably is seatedbehind and higher than the driving passenger in the front first seat 14.This allows the rear passenger to have a better line of sight, which isespecially important to military users, when the passenger in the secondseat 18 may be operating a weapon to defend the multimodal vehicle 2.

Frame:

The vehicle is approximately 77″ high, measuring from the top 20 of theframe 22 to the ground, with inflated 29″ tires 10. The multimodalvehicle frame 22 is about 58″ wide at its widest part, about 155″ longfrom a front 24 of the frame 22 to a back 24 of the frame 22, with thefront 24 being with relation to the forward driving direction of themultimodal vehicle 2. The multimodal vehicle 2 preferably weighs betweenabout 1,000 lb and 1,450 lb, and more preferably between 1,050 lb and1,150 lb.

Ground Engine:

The ground engine 8 is preferably an internal combustion engine,preferably with a power to weight ratio of approximately 0.4 hp/lb ofweight or greater (hp and torque values are max values unless otherwisestated). The ground engine 8 could be, for example a twin cylinder,single or double overhead cam, with 4 valves per cylinder, and twinbalance shafts with a high flow airbox and dual bore throttle body suchas an 89 hp, 66 ft-lb torque, 952 cc Prostar™ 1000, or a 110 hp, 70 ftlbs of torque, 999 cc Prostar™ RZR® XP 1000 EPS turbo, for example. Theground engine 8 could also be other internal combustion engines. Theground engine 8 is preferably at least 65 horse power and/or at least 50ft-lbs torque, more preferably at least 75 horse power and/or at least55 ft-lbs torque, most preferably at least 85 horse power and/or atleast 65 ft-lbs torque. In further embodiments, the ground engine 8could be one or more electric motors and or hybrid engines in additionto or in place of one or more internal combustion engines. In situationswhere the ground engine 8 includes multiple motors or engines poweringthe ground tractions elements 10, the total horse power and/or totaltorque powering all of the ground traction elements 10 will preferablybe at least 65 horse power and/or at least 50 ft-lbs torque, morepreferably at least 75 horse power and/or at least 55 ft-lbs torque,most preferably at least 85 horse power and/or at least 65 ft-lbstorque.

Propeller Engine:

The propeller engine 4 is preferably an internal combustion engine,preferably with a power to weight ratio of approximately 0.6 hp/lb ofweight or greater. The propeller engine 4 could be, for example, anormally aspirated, air- and water-cooled, horizontally opposedfour-cylinder, four-stroke, gear reduction-drive engine commonly used oncertified aircraft, light sport aircraft, ultralight aircraft andunmanned aerial vehicles, such as a Rotax® 912 100 hp, 1352 cc, with 97ft-lbs torque engine, or a Rotax® 914 115 hp 1211 cc engine, or afour-cylinder four-stroke, horizontally-opposed, turbocharged, air andliquid-cooled, gasoline engine design, with a mechanical gearboxreduction drive, and with a turbocharger having a compression ratio of3.5:1 and a critical altitude of 15,000 ft (4,572 m), employing dualelectronically controlled fuel injection, using dual channel RockwellCollins® ECUs, with dual ignition, such as a Rotax® 915 iS 135 hpengine. The propeller engine 2 could be other internal combustionengines. The propeller engine 2 is preferably at least 65 horse powerand/or at least 50 ft-lbs torque, more preferably at least 75 horsepower and/or at least 55 ft-lbs torque, most preferably at least 85horse power and/or at least 65 ft-lbs torque. In further embodiments,the propeller engine 4 could be one or more electric motors and orhybrid engines in addition to or in place of one or more internalcombustion engines. In situations where the propeller engine 4 includesmultiple motors or engines powering the propeller, the total horse poweror total torque powering the propeller will preferably be at least 65horse power and/or at least 50 ft-lbs torque, more preferably at least75 horse power and/or at least 55 ft-lbs torque, most preferably atleast 85 horse power and/or at least 65 ft-lbs torque.

The propeller engine 2 is preferably located adjacent to the back 26 ofthe multimodal vehicle 2, along the vertical midline plane 16, andattached to the propeller 6. The propeller engine 4 preferably extendsabout 4 inches behind the farthest back 26 portion of frame 22, whichaids in allowing normal flex room for the propeller 6 during operationof the multimodal vehicle 2 without striking the frame 22 or the wheelsor tracks 10. A propeller centerline 28 is preferably 20 inches abovethe ground engine 8. The propeller engine 2 is preferably axially spacedbehind and vertically spaced above the ground engine 8. In a preferredembodiment the propeller engine is spaced 28 inches behind ground engine6.

Engines Location:

The ground engine 6 is preferably at least 15 inches forward of thepropeller 6. In the preferred embodiment the ground engine 8 is at least21 inches forward of a back 26 of the frame 22 and at least 6 inchesforward of a rear axle 30. The ground engine 8 is preferably centeredalong a midline plane 16. The crankshaft 32 of the ground engine 8 ispreferably parallel to and co-planar along a horizontal rear axle plane34 as the drive shaft 36. Alternatively the crankshaft 32 may beco-axial with the drive shaft 36. The drive shaft 36 is preferablyorthogonal to the rear axle 30, and intersects the rear axle 30 at therear differential 38. In a preferred embodiment, the ground engine 8passes torque and speed through the crankshaft 32 to a continuouslyvariable transmission 40, which changes speed and torque as desired. Thecontinuously variable transmission 40 and the ground engine 8 bothpreferably lie in the rear axle plane and the midline plane 16. Though acontinuously variable transmission 40 is preferred, other transmissions40 such as transmissions having multiple defined gears may also be used.The continuously variable transmission 40 passes the torque and speed todrive shaft 36, which then passes it to the rear differential 38, thento the rear axle 30, and then to the wheel or track ground tractionelements 10. The ground engine 8 preferably extends between 8 and 15inches and more preferably 12 inches below a base 42 of the frame 22.The ground engine 8 preferably extends between 4 and 12 inches and morepreferably 8 inches below the rear axle 30. The ground engine ispreferably between 16 and 9 inches and more preferably 12 inches abovethe ground. A base guard 44 may extend under the ground engine 8 toprovide a level of protection for the ground engine 8 from groundobstacles during off road driving. By nature of the ground engine 8being lower and forward of the back 26 of the frame 22, the multimodalvehicle 2 is made more stable for driving off road by moving the centerof gravity lower and toward the center of the multimodal vehicle 2. Ifthe ground engine 8 were spaced even further from the rear axle 30though, the multimodal vehicle 2 would disadvantageously be required totake on more weight from because a longer drive shaft 36 would berequired. The ground engine 8 and the ground traction elements 10 arepreferably not mechanically functionally connected to the propellerengine 4. The propeller is preferably not mechanically functionallyconnected to the ground engine 8. This provides for more simplisticdesigns, less parts, and a lighter dual engine multimodal vehicle 2.

The value of separate propeller and ground engines 4, 8 includesredundancy, reliability, serviceability and reduced take-off roll,especially for government agencies, via using both engines 4, 8 duringtakeoff. Additional benefits conferred are a greater longevity of parts,a lower center of gravity and increased stability during off-road and inthe air. Some design logic of the dual engine design are increasedreliability, redundancy, safety, simplicity, and serviceability. As toredundancy and reliability, the axels, differential 38, engines 4, 8,and tires 10 make it difficult for the multimodal vehicle 2 to becomeimmobilized. With two engines 4, 8, failure to one does not necessarilymean failure to the multimodal vehicle 2. If the rear axle 30 isdamaged, the multimodal vehicle 2 could continue to operate via thepropeller engine 4. If one or both differentials 38 are lost, themultimodal vehicle 2 could still operate via the propeller engine 4.According to a preferred embodiment, the vehicle has attained higherground speeds with the propeller engine 4 alone and the ground engine 8in Neutral, versus the ground engine 8 alone. If one engine 4, 8 islost, the second engine 4 8 will keep the multimodal vehicle 2operational, at least for ground transportation, but if the propellerengine 4 is still operational, both ground and air transportation arestill possible. For serviceability, the multimodal vehicle 2 preferablyutilizes readily available parts, such as from the Polaris Company,which also brings parts familiarity to individuals servicing themultimodal vehicle 2, such as with certified Polaris techs, even thoughthe multimodal vehicle 2 vehicle is novel and inventively different thananything a person of ordinary skill in the art has seen before.Additionally, by using readily available parts when possible toconstruct the multimodal vehicle 2, the multimodal vehicle 2 gains alevel of global parts accessibility and servicing familiarity, even withthe inventively new multimodal vehicle 2.

Wing:

The wing 12 is preferably a single rectangular ram-air parafoil 12, alsocalled a ram-air parachute, measuring preferably between 500 and 600square feet in surface area. The ram-air parafoil 12, when inflated,resembles a low aspect ratio wing. It is preferably entirely constructedfrom fabric with no rigid members. The wing 12 has upper and lowermembrane surfaces 46, 48, an airfoil cross section, and a rectangularplanform. The airfoil section is formed by airfoil shaped ribs 50 sewnchordwise between the upper and lower membrane surfaces 46, 48 at anumber of spanwise intervals forming a series of cells 52. The surfacearea of the upper membrane surface 46 is understood to equal the surfacearea of the wing 12. The leading edge 54 of the wing 12 is preferablyopen over its entire length so that ram air pressure maintains the wing12 shape. The ribs 50 usually have apertures cut in them. This allowsthe transmission of pressure from cell 52 to cell 52 during inflationand pressure equalization after. The fabric used in the manufacture ofram-air parafoils 12 is preferably substantially nonporous to avoidpressure loss during use.

Operation:

With the wing 12 stowed, the multimodal vehicle 2 may be driven on theground as an all-terrain vehicle, off road over rough terrain and atspeeds up to 70 mph or more carrying a payload of around 350 lbs. Thisability to accelerate quickly and drive off road at high speeds isespecially important to military and first responders. The multimodalvehicle 2 preferably drives with typical automobile controls such asfoot accelerator and foot brakes 56 to control the ground speed, and asteering wheel 58 to turn the direction of the front wheels 12.

To quickly convert from ground operation to flying, the multimodalvehicle 2 is preferably stopped and the wing 12 is attached to thevehicle at the center of gravity (CG) bracket 60 via cords 62. Adistance between the two CG brackets 62 on either side of the multimodalvehicle 2 is preferably between 55 and 70 inches, more preferablyapproximately 60 inches. With the propeller 6 stationary (not rotating),the wing 12 is then stretched out behind the multimodal vehicle 2, withthe chords 62 over the fin 64. The ground engine 8 is then engaged andthe multimodal vehicle 2 accelerates forward. The wing 12 quicklyinflates and rises above the multimodal vehicle 2 moving the cords outof the propeller path 66. The distance separating the two CG brackets 60is preferably are more narrow than the width of the propeller path 66.The propeller engine 4 may then be engaged to turn the propeller 6 inaddition to the ground engine 8 directly powering the wheels 10 to evenmore rapidly accelerate the multimodal vehicle 2 and approach a liftvelocity. Normally, in less than 300 feet the multimodal vehicle 2 willtake flight, the ground engine 8 may be turned off, and the multimodalvehicle 2 will be powered by the propeller engine 4 turning thepropeller 6. Such a fast and short distance take off is important tomilitary and first responders when time is of the essence and onlylimited substantially flat terrain may be available. Also, this dualengine method of take-off allows for no prop-guard to be used, whichsaves unnecessary weight from the multimodal vehicle 2. The multimodalvehicle 2 may also take-off and fly without a mast or other rigid wingattachments to hold up the wing 12, which can be dangerous to thepropeller 4 if the mast breaks off during flight, which would takeadditional precious time to set up, which would constitute additionalweight, and which would likely rub on the wing 12 and cause prematurerips or other failure in the wing 12. Once in flight, the multimodalvehicle preferably requires only two flight controls—handles for leftand right steering and throttle to climb or descend. The throttle may bea peddle or a hand throttle 70.

The multimodal vehicle 2 preferably has two fuel tanks 72, one placed oneach side of the multimodal vehicle 2, to power the ground engine 8 andthe propeller engine 4. The two fuel tanks 72 are preferably filled witha common fuel for both ground and propeller engines 4, 8. The two fueltanks 72 may be fluidly connected to one another, such that fuel fromeither tank may go to either engine 4, 8, so that the maximum range maybe obtained from the multimodal vehicle 2 no matter what mode themultimodal vehicle 2 travels—ground or air. This is also a benefit tomilitary and first responders, as it is not always predictable ahead oftime what mode the multimodal vehicle 2 will need to travel in to bestachieve a given mission.

The invention illustratively disclosed herein suitably may explicitly bepracticed in the absence of any element which is not specificallydisclosed herein. While various embodiments of the present inventionhave been described in detail, it is apparent that various modificationsand alterations of those embodiments will occur to and be readilyapparent those skilled in the art. However, it is to be expresslyunderstood that such modifications and alterations are within the scopeand spirit of the present invention, as set forth in the appendedclaims. Further, the invention(s) described herein is capable of otherembodiments and of being practiced or of being carried out in variousother related ways. In addition, it is to be understood that thephraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items while only the terms “consisting of” and“consisting only of” are to be construed in the limitative sense.

What is claimed is:
 1. An air and land multimodal vehicle comprising: aframe; a propeller engine attached to a first location of the framesupplying power and torque to a propeller; a rear-mounted ground engineattached to a second location of the frame supplying power and torque toone or more ground traction elements; a flexible wing releasablyconnectable to the frame; a drive shaft coupled to the ground engine andbeing parallel to a centerline of the propeller; wherein the propellerengine is vertically and horizontally spaced from the ground engine;wherein the propeller engine and the ground engine are both aligned witha vertically extending medial plane of the multimodal vehicle bisectingthe multimodal vehicle from a front of the multimodal vehicle to a backof the multimodal vehicle; wherein the ground engine extends at least 6inches below a base of the frame.
 2. The multimodal vehicle of claim 1wherein the flexible wing is a ram air parafoil, the ground engine doesnot directly supply torque to the propeller, and the propeller enginedoes not directly supply torque to the one or more ground tractionelements.
 3. The multimodal vehicle of claim 2 wherein a surface area ofthe ram air parafoil is between 500 square feet and 600 square feet. 4.The multimodal vehicle of claim 1 further comprising a horizontal rearaxle plane which extends parallel to the ground and relative to theground when the one or more ground traction elements are in contact withthe ground, and a rear axle and the ground engine lying in thehorizontal rear axle plane.
 5. The multimodal vehicle of claim 4 furthercomprising a continuously variable transmission functionally connectingthe ground engine to the rear axle, and the continuously variabletransmission lying in the rear axle plane.
 6. The multimodal vehicle ofclaim 5 wherein the drive shaft extends from the continuously variabletransmission and connects to a differential of the rear axle, the driveshaft transmitting power and torque from the continuously variabletransmission to the rear axle and the ground traction elements of themultimodal vehicle.
 7. The multimodal vehicle of claim 6 wherein thedrive shaft lies in the rear axle plane.
 8. The multimodal vehicle ofclaim 1 wherein each of the propeller engine and the ground engineprovides at least one of 65 horse power or at least 50 ft-lbs torque. 9.The multimodal vehicle of claim 1 further comprising one or more seatsaligned with the vertically extending medial plane.
 10. The multimodalvehicle of claim 9 further comprising a first seat and a second seat,each seat being substantially bisected by the medial plane.
 11. Themultimodal vehicle of claim 10 wherein the second seat is horizontallybehind the first seat and is between 6 and 18 inches vertically higherthan the first seat.
 12. The multimodal vehicle of claim 1 wherein thepropeller lacks a propeller guard.
 13. The multimodal vehicle of claim 1wherein the propeller engine and the ground engine are fluidly connectedto a common fuel reservoir.
 14. The multimodal vehicle of claim 1wherein a base guard extends under the ground engine to protect theground engine.
 15. The multimodal vehicle of claim 1 wherein thepropeller engine extends at between 3 inches and 8 inches behind afarthest portion of frame; the propeller centerline is between 15 inchesand 25 inches above the ground engine, and the propeller engine isspaced 28 inches behind ground engine.
 16. The multimodal vehicle ofclaim 1 wherein the multimodal vehicle has a dry weight of between 1,000lbs and 1,450 lbs and the ground traction elements are one of wheels ortracks.
 17. The multimodal vehicle of claim 1 wherein the ground enginehas a crankshaft that is parallel to the centerline of the propeller.18. The multimodal vehicle of claim 17 wherein the crankshaft is coupledto a continuously variable transmission, which is coupled to the driveshaft, which is coupled to a rear differential.
 19. The multimodalvehicle of claim 18, further comprising a drive axle that is orthogonalto the drive shaft.